Precast concrete building panels provide advantages for many applications in that construction time and forming requirements for preparation of panels are reduced. Such panels may be prepared by casting them in a suitable mold on a horizontal surface, preferably an already cast floor slab at the construction site. Upon curing, the cast panels are then erected into final position by means of a crane using "tilt-up" construction techniques. My prior patent, U.S. Pat. No. 4,871,702, issued June 27, 1989, discloses precast panels that include a rigid internal slab of insulating material, the panels being formed by providing grooves in an upper face of the slab, placing its lower face over a layer of particle board or the like, and pouring concrete to provide a layer over the upper face and into forms around the edges of the slab. Concrete poured into the grooves forms supporting ribs which, together with the concrete edge frames, give the panels necessary strength.
Panels adapted for use in ceilings or roofs are disclosed in my co-pending application Ser. No. 071,371,915, filed June 27, 1989. These panels are generally similar to those described above except that the panels which are to be disposed adjacent to one another at interior locations away from the ceiling or roof edge do not have precast edge frames at such locations. Edges without edge frames are sealably joined together after being placed in an array.
Requirements exist for insulated concrete panels that would have concrete layers on both faces of an insulating slab instead of only one face, as is the case for the panels described above. Concrete faced interior wall surfaces may be preferred over wood faced surfaces for applications such as warehouses and industrial buildings. Panels for walls of these buildings are often needed in long lengths such as 24 feet or more, and the additional strength that would be provided by another layer of concrete as well as by internal ribs in grooves in the slab on one face and concrete intermeshed with slab ridges on the other face would enhance the capability of long-span panels to be lifted and guided into position without breaking. In addition, high strength such as to provide the panels with load-bearing capability may be desired.